Electrical apparatus, as for model railroads, including resonant relay and switches therefor



g 9, 1955 c. c. KLEMME 2,714,859

ELECTRICAL APPARATUS, AS FOR MODEL RAILROADS, INCLUDING RESONANT RELAY AND SWITCHES THEREFOR 3 Sheets-Sheet 1 Filed Oct. 17, 1949 INVENTOR.

ATTORNEYS Aug. 9, 1955 c. c. KLEMME 2,714,859

ELECTRICAL APPARATUS, AS FOR MODEL RAILROADS, INCLUDING RESONANT RELAY AND SWITCHES THEREFOR Filed 001;. 17, 1949 5 Sheets-Sheet 2 INVENTOR. CLAUDE C. KLEMME BY 51W *MW ATTORNEYS Fig. 10

2,714,859 INCLUDING Aug. 9, 1955 ELECTRICA 3 Sheets-Sheet 3 Filed Oct. 17, 1949 an o ET UA Q L EL m 8 F m w A F R Y 0 m R 0 Q T A R L F L C S D 0 D U A Q m m m m CLAUDE C. KLEMME W MV ATTORNEYS United Sttes Patent ELECTRICAL APPARATUS, AS FOR MODEL RAIL- ROADS, INCLUDING RESONANT RELAY AND SWITCHES THEREFOR Claude C. Klernme, Boulder, Colo.

Application October 17, 1949, Serial No. 121,798

9 Claims. (Cl. 104150) This invention relates to electrical apparatus including resonant relays and switches therefor, and more particularly to electrical apparatus for remote control and similar operations, to resonant relays which are responsive to audio-frequency signals, and to switches especially adapted for use in such relays and electrical apparatus.

In model railroads, for instance, it is often desired to direct, by remote control, various operations of a train, such as starting or stopping or the speed or direction of the engine drive motor, or the operation of uncoupling devices, lights, horns, whistles, and the like. For this purpose, a signal wave may be superimposed on the current supplied to the train through the tracks, such current normally being direct current. Other control operations, such as the starting or stopping of a motor, the opening or closing of a valve or other device in a manufacturing or chemical plant, or which involves the sending or receiving of control or other signals from remote points may be carried out by use of a signal wave. For a purpose of this type, use has been made of a relay which includes a vibrating reed. Previous relays of this type have, in general, been too large in bulk and too heavy in weight to be accompanied successfully, either in the engine tender or in a model train car. Also, such previous relays have normally required sensitive secondary relays because the current which can be controlled is too small to actuate directly control devices, such as solenoid operated switches, of any appreciable size. Thus, one or more stages of amplification, with attendant higher initial cost, upkeep and space occupied, are often necessary. A reed or the like may also be utilized in measuring or indicating vibrations of the parts of structures, such as a bridge girder or column, a machine part, or the like, and the apparatus of this invention also may be adapted for use in such situations.

Among the objects of this invention are to provide a novel relay and novel electrical apparatus; to provide novel apparatus which includes a plurality of relays; to provide apparatus which includes a vibrating reed and a switch which are associated together in a novel manner; to provide a novel switch particularly useful for use with a vibrating reed or the like; to provide apparatus consisting of several relays, adapted to operate in conjunction with a single vibrator which is responsive to more than one signal wave or the like; to provide apparatus including one or more relays and which is particularly adapted for use in model trains and the like; to provide such apparatus which is relatively small and also relatively light in weight, and therefore can be incorporated quite easily in an engine tender or a car of a model train; to provide such apparatus which may be made in any one of several different forms; to provide such apparatus which is positive in operation and may include a relay coil which need not be particularly sensitive and there fore may be made relatively light in weight; and to provide apparatus which is applicable generally to various remote control or signaling operations.

Additional objects of this invention and the novel features thereof will become apparent from the following description, taken in connection with the accompanying drawings, in which:

Fig. 1 is a perspective view, partly diagrammatic, illustrating relay apparatus constructed in accordance with this invention which includes a relay switch shown in non-activated or closed position;

Fig. 2 is a similar perspective view, partly diagrammatic, illustrating the actuation of the relay when the switch is open;

Fig. 3 is an enlarged top plan view of a switch which is alternative to the switch of Fig. 1;

Fig. 4 is a top plan view of a further alternative switch;

Fig. 5 is a side elevation, on a reduced scale, of a vibrating reed and switch construction alternative to that of Fig. 1;

Figs. 6 and 7 are end and side elevations, respectively, showing slightly different arrangements of certain parts of the relay of Fig. 1;

Fig. 8 is a diagram of the off track portion of a circuit for controlling the operation of a model railroad train or the like, utilizing apparatus constructed in accordance with the invention;

Fig. 9 is a diagram, with certain parts in perspective, illustrating the on track portion of the circuit and especially those parts which may be installed on the tender of an engine or on a car of a model railroad train;

Fig. 10 is a diagram, with certain parts in perspective, of a simplified model train installation; and

Fig. 11 is a perspective View, partly diagrammatic, illustrating the use of the switch of Fig. l as an .amplifier.

In general, as in Figs. 1 and 2, relay apparatus constructed in accordance with this invention includes a switch S,

a which in turn includes a relatively light blade 10 and a relatively heavy or weighted blade 11, which also may be rigid. The light blade 10 may extend beyond the heavy blade 11 and is adapted to be engaged by a vibrating member, through which no current passes, such as a reed 12, during vibration of the latter. The reed 12 may be mounted on the diaphragm 13 of a vibrator V, such as a telephone receiver or similar device, to which current is supplied by leads 14 and 15. The heavy blade 11 may be provided with a weight 16, or otherwise formed or mounted so as to have a considerably greater inertia or immobility than the light blade 10 so that, as shown in Fig. 2, during vibration of the reed 12, as from the dotted to the full position, the light blade 10 will tend to move away from the heavy or immobile blade 11, thus breaking the contact between the end 17 of the heavy blade and the light blade during each vibration of the reed 12. Thus, the light blade 10 tends to move between the dotted and full positions thereof in Fig. 2, and although the heavy blade 11 tends to follow the light blade 10, the inertia or rigidity of blade 11 is such that it will not follow the light blade. That is, from the dotted position of Fig. 2, the reed on its forward stroke will engage the light blade 10, and the light blade will be pushed away from the heavy blade 11 and moved to the full position. On its return stroke, the reed will tend to move away from the light blade and the light blade will return to the heavy blade, as in the dotted position. However, the amount of time that the light and heavy blades are in contact during vibration of the reed is relatively small, so that the amount of current which passes between the light and heavy blades is quite small. Stated in another way, the resistance of the heavy and light blades to current passing therebetween, may increase from a very small value when the reed is at rest, to a relatively high average value during vibration of the reed. In a relay constructed in ac cordance with this invention, such resistance as measured by an ohmeter increased from 3 ohms with the reed at rest, to between 500 and 1,000 ohms during vibration of the reed.

In order to maintain adequate contact between blades 10 and 11 when the reed 12 is at rest, as in Fig. l, the blades 10 and 11 are held together with a sutficient degree of force, as by the blades being mounted in an insulating block 18 with a slight initial compression of both blades but insuflicient to cause blade 11 to move more than a small fractional distance when reed 12 engages the light blade. The end 17 of heavy blade 11 may be curved toward the light blade 10, to provide point or line contact at the extreme end thereof. Also, as shown in Fig. 1, when at rest the reed 12 is normally disposed a short distance away from the end of the light blade 10, but is sufficiently close that during vibration the reed will need to travel only a short distance before striking the light blade. The heavy blade 11 and light blade 10 may be made of thin strips of the same electrically conductive material, preferably having sufiicient resilience to have spring-like qualities, Phosphor bronze having been found suitable. Suflicient inertia of the heavy blade 11 may be provided by attaching thereto, as by soldering or welding or forming integrally therewith, the weight 16 which is preferably disposed adjacent the outer end 17 to produce as great an inertia effect as possible.

In further accordance with this invention, the switch including blades 10 and 11, through suitable electrical conductors, is placed in parallel with a relay coil 20 in an electrical circuit, which may also include a source of current for the relay coil and the blades, such as a battery 21, as Well as a regulating resistance 22. A switch 23, normally open but adapted to be closed by the relay coil 20, is included in a load circuit to which current may be supplied from any suitable source, such as a battery 24, switch 23 and battery 24 being in series with a load represented by a lamp 25, but which may be any desired type of load, such as a reversing switch coil for an engine motor of a model train, a control for starting or stopping a motor or opening or closing a valve used in an industrial plant or the like, or the control for a whistle, horn, or other device on a model railroad train.

While reed 12 is at rest, as in Fig. l, the current from battery 21 will pass primarily through blades 10 and 11, since the resistance of the latter is relatively low when in contact, as compared with the resistance of relay coil 20. While a small amount of current will pass through relay coil 20, the same will be insufficient to produce a sufliciently strong magnetic field to close switch 23. However, when the reed 12 vibrates, as in Fig. 2 and the average resistance of the contact between blades 10 and 11 increases tremendously, such as from 3 ohms to between 500 and 1,000 ohms as indicated previously, a sufiicient amount of current will pass through relay coil 20 to close switch 23 and light lamp 25, or operate any other load or control device in its place.

The vibrator V may be similar to a telephone receiver, being of a conventional type so that the interior construction thereof is not shown. When an alternating current of a suitable frequency, or a modulated direct current, is supplied through leads 14 and 15, the diaphragm 13 will begin to vibrate. Whenever the period of vibration of diaphragm 13 corresponds to the natural frequency of vibration of the reed 12, the reed 12 will vibrate and thereby cause suiiicient current to pass through relay coil 20 to close switch 23, with the results indicated above.

As in Fig. 3, special contacts 27 and 28, such as silver, may be placed on the blades 10 and 11, otherwise similar to blades 10 and 11 of Fig. 1, to insure as long life as possible of the contacts, although normally the amount of current passing between the blades is relatively small. Particularly if higher voltages are handled, it may be desired to utilize such contacts.

As in Fig. 4, a rigid bar 29 may be substituted for the heavy blade, and a light blade 3i may be provided with a slightly curved end 31, which extends past the end of bar 29, as shown, for engagement by the vibrating reed 12. Or, the reed may be disposed between the switch members, such as in the dotted position 12' of Fig. 4. The end 32 of bar 29 may also be curved toward blade 30 to insure contact. The resilient lighter blade fail is held by an insulating block 18, or other suitable mounting device, in which the bar 29 may also be mounted, and a slight initial compression of blade 30 against bar 29 is provided, so that adequate electrical contact will be maintained between end 32 of bar 29 and blade 30 when the latter is at rest. When the reed or other vibrating member vibrates, the rigid bar 29 will, of course, remain solid and will not tend to follow the light blade 30. Thus, the switch of Fig. 4 can be connected in parallel with a relay coil, to achieve results similar to that achieved by the arrangement of Figs. 1 and 2.

In addition to the modifications of Figs. 3 and 4, other variations of the switch may be employed, as well as different arrangements in relationship of the switch and the vibrating reed. Thus, as illustrated in Fig. 5, a switch S may extend parallel to the reed 12, instead of perpendicularly thereto as in Fig. l. A heavy blade 11 may be formed as before, while a light blade 10 may be curved and then extend laterally at the end 33, as shown,

) so as to be engaged by the reed 12 when the latter is vibrated by a signal of suitable frequency received by the vibrator V, or similar device, through leads 14 and 15. Or, as in Fig. 6, the switch S may be disposed parallel to the reed 32, but in substantial alignment therewith, and with the reed 12 spaced slightly from the end of the light blade 10, when at rest. However, reed 12 will engage the light blade durin vibration, in substantially the same manner as indicated in Fig. 2. Again, as in Fig. 7, the switch S may be disposed angularly with respect to the reed 12, the slight spacing between the reed and the light blade being substantially as before. In each of the arrangements of Figs. 5, 6 and 7, as well as in the case of the switches of Figs. 3 and 4, the switch may be included in a relay circuit similar to that of Figs. 1 and 2, that is, in parallel with a relay coil and adapted to increase in average resistance tremendously upon vibration of the reed or other vibrating member, so that a suiilcient current will flow through the relay coil to close a switch controlled thereby, or operate any other type of control device or mechanism.

It will be evident from the foregoing forms thereof, that the switch of this invention comprises a readily movable member and a relatively immobile member, each electrically conductive and the readily movable member being adaoted to be engaged by a vibrating member or the like. The point of engagement of the vibrating member may be the extending end of the readily movable member, or an intermediate point, the principal requirement being that the movement of the readily movable member, occasioned by the vibrating member, diminish the contact between the switch members. Thus, the vibrating member, such as a reed, may be disposed be tween the switch members. The readily movable switch member is preferably relatively resilient so as to maintain contact with the other switch member when at rest, and may be a blade, either straight or curved, although it may be a helical, conical, or spiral spring, having a uniform or varying cross-section, as desired. The relative immobility of the other switch member may be due "1 to inertia, as by its Weight or a Weight attached thereto,

or may be due to its stiffness or rigidity.

As will be understood, in lieu of relay coil 20 of Figs. 1 and 2, or the corresponding relay coil of a circuit in which any of the switches of Figs. 3 to 7 are included, another electrical element, such as an indicating device may be substituted. Such a device may be a signal lamp, adapted to indicate the existence of vibration of a reed or other element adapted to move the light blade. Thus, a bridge column or girder, or a machine part, which may be subject to vibration, may be the vibrating member and may be positioned to engage the light or readily movable blade in order to indicate overloading, undue amplitude of vibration or the like, although it may be preferred to mount areed which is responsive to a specific frequency of vibration upon the bridge column or girder, machine part, or the like, particularly when the vibration frequency will reflect the condition to be detected with sufficient accuracy.

The apparatus constructed in accordance with this invention may be utilized in remote control operations, as by being incorporated in the circuits illustrated diagrammatically in Figs. 8 and 9. In general, a control wave of a suitable audio frequency may be carried by a carrier wave of radio frequency which is transmitted independently or superimposed on a power current, such as a current supplied through the track to a model railroad train. The power current may be low frequency alternating or direct current. The transmitting or off track portions of such a circuit are illustrated in Fig. 8 and the receiving or on track portions in Fig. 9, the former including a motor generator or other suitable source of power current for wires 36 and 37 leading to the track. Choke coils 38 are interposed between the motor generator 35 and the source of radio frequency current, connected through wires 39 and 40, to prevent the radio frequency current from passing through the motor generator set, while a condenser 41 is placed in each of lines 39 and toblock the direct or power current from the frequency supply circuit. A modulated radio frequency current may be supplied by suitable conventional devices, such as an audio frequency oscillator adapted to modulate the radio frequency current supplied by any suitable radio frequency oscillator, the oscillators being supplied through line wires 42, 43, 42' and 43 with suitable current, such as 110 to 120 volts A. C. Any suitable tuning device may be used to produce modulations of a desired frequency, the frequency being changed to different values to actuate the different devices to be controlled. Such change in frequency may be obtained by a tuning condenser (not shown), or through pushbuttons 44, which connect different condensers to the circuit.

In the receiving portion of the circuit shown in Fig. 9, it will be understood that wires 36 and 37' are, in effect, continuations of wires 36 and 37 of Fig. 8. It will be understood, of course, that more than one set of wires 36' and 37 may be utilized, as for supplying power to different portions of a model train, although most of the devices to be controlled will normally be installed in either the engine or the tender. As in Fig. 9,. the wire 36 is provided with a choke coil 38' to prevent the flow of the superimposed high frequency current to the loads, indicated generally as lamps 25a, 25b, 25c, and 25a, but which may be an engine speed adjusting device, the forward or reverse windings of the engine drive motor, or a whistle, horn, uncoupling device and the like. The loads 25a, 25b, 25c and 25d are controlled by an equal number of switches, such as switches Sa, Sb, Sc, and Sd, the corresponding reeds 12a, 12b, 12c and 12d, respectively, being mounted on the diaphragm 13 of a vibrator V of a conventional nature, as indicated. previously. The high frequency portion of the circuit of Fig. 9 includes the primary coil 45 of a radio frequency transformer, to which the high frequency current is supplied by leads 46 and 47 from the wires. 36' and 37, a

condenser 48 being interposed in lead 47 to block di-- rect current. Through leads 50 and 51, the secondary coil 49 of the transformer supplies the modulated radio frequency current to a copper oxide rectifier 52, from which the current modulations are supplied through leads 14' and 15 to the vibrator V. Each of the reeds 12a, 12b, 12c and 12d, is responsive to a particular frequency which is preferably allocated so that no one of the reeds will be resonant to any harmonic of a frequency to which one of the other reeds is resonant. In any event,

rug

when the audio frequency oscillator of Fig. 8 is tuned to a specific frequency or frequencies, corresponding to the resonant frequency of one or more of the reeds 12a, 12b, 12c or 12d, each reed involved will begin to vibrate, and the corresponding switch Sa, Sb, Sc or Sd will increase in average resistance so that the corresponding relay coil 20 will close the corresponding switch 23, thereby permitting current to flow through the corresponding load 25a, 25b, 25c or 25d. In the circuit of Fig. 9, full power current is supplied to the loads 25a, 25b, 25c and 25d, each of which is in series with a switch 23 and connected across wire 36 and an auxiliary wire 53, the latter of which is connected to wire 37'. Each relay coil 20 and the corresponding switch Sa, Sb, Sc or Sd is connected in parallel, as a unit, as shown, while the four units are connected in series with a resistor 54, adapted to limit the amount of current flowing through the switches and relay coils. As will be evident, with all of the switches Sa, Sb, Sc, and Sd closed, i. c. with the corresponding reeds 12a, 12b, or 12d at rest, the current will flow from line wire 36 through the resistor 54 and primarily through each switch in turn, to line wire 37'. However, when one of the reeds vibrates, the average resistance of the corresponding switch will increase, so that sufficient current will flow through the corresponding relay coil 20 to close the switch 23 associated therewith, thereby causing current to pass to the corresponding load 25a, 25b, 250 or 25d.

While the diaphragm 13 of the vibrator V will normally be vibrated at only one control frequency, i. e., that of reed 12a, 12b, 12c or 12d, two or more frequencies can be transmitted simultaneously to actuate more than one reed. The reeds are preferably responsive to 21 vibration in the audio frequency range, so that the length of the reeds will not be unduly short or long. The radio frequency carrier current is produced in a much higher frequency range, such as about 300,000 cycles per second, for example. The number of reeds and switches associated with a single diaphragm may be greater or less than four, while more than one vibrator may be mounted at different points in a model railway train, so that a number of devices at different points may be controlled at the same time. Due to the relative lightness in weight of the vibrator V, and particularly the relay coils 20, which need not be particularly sensitive and therefore do not require a relatively large weight of winding and also may be relatively small in size, all of the parts illustrated in the on track circuit of Fig. 9 are readily mounted in the tender or a car of a model railroad train. In a specific installation, in accordance with the present invention, the radio frequency transformer, condenser, rectifier, choke coil, vibrator, reeds and switches, and also the relay coils 20 and switches 23, have been mounted in a space about 1%" wide and 3 /2" long, with space to spare, the total height of such equipment being about 1. Thus, all of the receiving equipment can be readily mounted on the tender of a model train, such as for H0 gauge track.

An example of an installation similar to that of Fig. 9, and utilized for the control of the engine drive motor of a model railroad train, is illustrated in Fig. 10. The operating current and superimposed control frequency are supplied to rails 55 and 56, as through a frequency oscillator off-track circuit of the type illustrated in Fig. 8, or any other suitable circuit. On the track, one pair of wheels 57 of a truck 58 roll on and contact rail 55, as one side of the line, the wheels and truck being connected with wire 37' from which a high frequency lead 46 extends. The opposite wheels of truck 58 are insulated, so that engagement thereof with the opposite rail 56 will not cause a short circuit. Similarly, the wheels 60 of a second truck 61 engage rail 56, and are connected with line wire 36, while the opposite wheels of truck 61 are insulated so that their engagement with rail 55 will not cause a short circuit. The trucks 58 and 61 may be those of the engine or a car, or those of the tender, the remainder of the parts shown in Fig. 10 being on track and conveniently mounted in a tender or the like of a model railroad train. As before, the primary 45 of a radio frequency transformer is supplied by wires 46 and 47 from line wires 36' and 37, a condenser 48 being placed in series with primary winding 45, to prevent the flow of power current through the radio frequency circuit. Also, through wires 56 and 51, current from the transformer secondary 49 is supplied to a rectifier 52, the impulses therefrom being supplied through leads 14 and to vibrator V. As before, a series of reeds, such as reeds 12a, 12b, 12c and 12d, are mounted on the diaphragm 13 of vibrator V, each reed being responsive to a particular frequency of vibration of the diaphragm. Each of switches Sa, Sb, Sc and Sd is respectively adapted to be engaged by the corresponding reed, and also is placed in parallel with relay coil 2%, 26b, 200 or d, respectively. The switches 23 LOT relay coils 20a and 2011 are not indicated as controlling a load, but it will be understood that any desired signal or model train device may be controlled thereby.

The relay coils 29c and 26d, respectively, control a pair of signal throw, double pole switches 123 and 123, which are cross connected by leads 62 and 63 with a control motor 64, mechanically connected by an insulating coupling 65 with a screw 66. The control motor 64 may be a series motor, instead of a permanent magnet motor, to overcome the effect of reversing the polarity of the tracks. As before, a choke coil 38 is placed in lead 36, to prevent the transmission of radio frequency current to the power portions of the circuit. Thus, beyond choke coil 38', a wire 67 extends to screw 66, While a wire 68 is connected with the switches 123 and 123. A resistor 54 may be placed in series with the reed actuated switches and relay coils, to limit the current flowing through the relays to a suitable value. Beyond resistor 54 a wire 69 extends to the far side of switch Sa, while wires 70, 71 and 72, respectively, connect the near side of switch Sa with the far side of switch Sb, the near side of switch Sb with the far side of switch Sc, and so on. Also, the opposite side of switch Sd is connected by a wire 73 with a branch line wire 74-, which also extends from line wire 37 and to switches 123 and 123. Beyond resistor 54, an additional wire 75 extends to the far side of relay coil 29a, in parallel relation with wire 69, while wires 76, 77 and 78, respectively, connect the near side of a succeeding relay coil with the far side of the next relay coil, and wire 79 the near side of coil 20d with wire 73. The parallel relationship between each switch and the corresponding relay coil is completed by a cross wire 86 connecting wires 70 and 76, cross wire 81 connecting wires 71 and 77 and cross wire 82 connecting wires 72 and 78.

The main drive motor 83 of the model train engine is a reversing motor, controlled by a double pole, double throw, snap action switch having poles 34 and 84, their fixed terminals being connected by wires 85 and 86 with the motor 83. The current supplied through wire 67 to screw 66 passes through a threaded block 87 which carries a contact 83 for a variable resistance 89, and thence through wire 90 to contacts 91 of the snap action switch. Block 87 also carries a plunger 92 adapted to reverse the snap action switch, whenever block 87 is moved to a predetermined position at or against the right hand end of screw 66. Such movement of block 87 will, of course, mean also that contact 88 will have moved to or near the end of variable resistance coil 89, thus placing all or nearly all of the resistance in series with the motor and reducing to a minimum the current supplied to the engine drive motor 83. The value of the resistance 89 is preferably such that the motor 83 will be stopped before the block 87 is run toward the right end of screw 66 far enough to cause the snap action switch to be actuated by plunger 92. which will cause the engine motor 83 to turn in the opposite direction, when block 87 is later moved back to the left by screw 66, so that a smaller amount of resistance 89 is in series with motor 83. In the full position shown in Fig. 10, pole 84 connects one side of motor 83, i. e., motor lead 86, with line wire 37, through contact 93 and wires 94 and 95; and pole 84' connects the opposite side of motor 83, i. e., motor lead 85, with the opposite line wire 36', through contact 91, wire 9!), variable resistance 89, screw 66 and wire 67. When the snap action switch is actuated to move poles 84 and S4 to the opposite position, pole 84 will engage contact 91 to connect motor lead 86 with line wire 36', while pole 84 will engage a contact 96 to connect the opposite lead of motor 83, through wires 97 and with line wire 37. Block 87 may be run backwardly and forwardly i open. When the diaphragm 13 of vibrator V is vibrated at a suitable frequency, reed 12c will vibrate, causing the resistance of switch Sc to increase and relay coil 226 to be energized, thereby closing switch 123 against contacts 98 and 99. This causes the winding of motor 64 to be connected in one direction between line wires 36' and 37, i. e. from wire 36' through wire 68, contact 98 and wire 62 to one side of the motor 64, and from the other side of the motor 64 through wire 63, contact 99 and wire 74 to line wire 37'. Assuming that the block 87 is moved to the left by such rotation of motor 64, continued rotation of control motor 64 will cause the speed of engine drive motor 83 to increase until full speed is reached, i. e., substantially all of resistance 89 will have been cut out, it being noted that the direction of motor 83 is determined by the position of the snap action switch. If a different frequency of vibration has been transmitted to vibrator V, so that reed 12d vibrates, the resistance of switch Sd will increase so that relay coil 20d will be energized sutficiently to close switch 123 against contacts 98' and 99, it being understood that the frequency for vibrating reed is discontinued so that relay coil 200 will be deenergized and switch 123 will open. Upon the closing of switch 123', the direction of rotation of motor 64 will be reversed, so that the block 87 will be moved to the right along screw 66, thereby causing the speed of engine drive motor 83 to be reduced. The speed of the model train may be increased and decreased, as desired, by actuating reed 12c and 12d, alternatively or the same reed intermittently. Continued actuation of reed 12d will cause the motor 83 to stop and then cause the plunger 92 to push the snap action switch to the opposite position, so that when reed 12c is again vibrated and relay coil 200 is energized, the motor 83 will be started, but in the opposite directionv As will be evident, the construction of Fig. 10 provides a relatively simple and effective construction for controlling the engine drive motor, utilizing only two vibrating reeds. However, more than two reeds can be used, as by one reed being utilized to increase the speed of the engine drive motor, another to decrease the speed, and a third to control the direction of movement of the motor. Or, two reeds can be used to control the direction of the movement of the engine drive motor, and the two other reeds for regulating speed by controlling the increase and decrease in speed, respectively.

The switch of this invention may also be utilized for amplification, such as in the manner illustrated in Fig. 11, wherein the light blade 10 of the switch S is in direct contact with the diaphragm 13 of a vibrator V, to which a controlled frequency current is supplied, as before,

through leads 14 and 15. In this form, the switch S is in series with a resistor 100 and a battery 101 or other source of current, the switch S modulating or causing variations in the current supplied through leads 102 and 103 to a second vibrator V, on the diaphragm 13 of which a reed 12 may be mounted. Reed 12. is, of course, adapted to engage a switch S2 similar to switch S and placed in relation to the reed in the same or a manner similar to that shown in Figs. 1 to 7. Switch S2 is preferably placed in parallel with a. relay coil 105 and the switch S2 and coil 105 connected to a suitable source of current, such as a battery 106. As will be evident, the vibratory impulses received by the vibrator V will be reflected in the modulations of the current supplied to the coil of vibrator V, with the same frequency of vibration, but a considerably heavier current may be employed so as to increase the force applied to the diaphragm 13 of vibrator V. Instead of a vibrator V, the switch S of Fig. 11 may engage a structural member or a machine part, so that where the period of vibration of the latter reaches the frequency to which reed 12 or vibrator V is responsive, an alarm or other signal, or a suitable safety device may be actuated.

From the foregoing, it will be apparent that the electrical and relay apparatus of this invention fulfills to a marked degree the requirements and objects hereinbefore set forth. The relay of this invention is positive in operation, yet is light in weight because it does not. require a particularly sensitive coil, since the average resistance of a switch constructed in accordance with this invention increases tremendously upon vibration of the relatively light blade or readily movable member. In the switch of this invention, the combination of a relatively resilient light blade, with a relatively heavy or rigid blade, produces a construction which will respond to, a relatively light impulse of a vibrating member, but is also positive in operation and is not materially afiected by differences in the amplitude of vibration of the vibrating member. The electrical apparatus of this invention, which may include a plurality of switches and relays, may be made very compact in size, since four or more reeds may be mounted on the same diaphragm and the switches grouped about them. Thus, due to the lightness, compactness and efiectiveness in operation, the relay apparatus of this invention is particularly useful in controlling the operation of model trains or the like, or for use in other situations where the foregoing attributes are desirable. By placing the switch of this invention in parallel with a relay coil, a novel relay construction is produced. This relay may include a coil which is much less sensitive than a coil which would be necessary if the current were passed between the vibrated member, such as one of the reeds mounted on the diaphragm, and a switch point, the vibration of the member being utilized to pass current through the relay coil and in series with the same. In an experimental construction of this type, it was necessary to utilize a 2,000 ohm relay coil to achieve any substantial results whatever. However, with a switch constructed in accordance with this invention in parallel with a relay coil, only a 100 ohm coil was necessary, utilizing the same control voltage, while the results secured were far superior, both with respect to positive control of the relay coil and with respect to permissible. variation in the amplitude or frequency of vibration of the vibrating member or reed.

It will be evident that various changes and different applications of the apparatus of this invention may be made. For instance, the electrical apparatus of this invention may be utilized in controlling model boats, unmanned boats, vehicles or aircraft, guided missiles and the like. Instead of passing a modulated radio frequency wave over a track circuit, a modulated radio wave may be transmitted by wireless. Also, the audio frequencies may be transmitted mechanically to the vibrating member which actuates the switch, and devices other than an audio frequency oscillator, such as one or more tuning forks, may be utilized in producing the audio fre quencies, waves or modulations. Various changes may also be made in the constructions illustrated. For instance, the vibrating reed or reeds may be mounted in a manner similar to that of a frequency meter, as on the base of a pole piece having a coil around an upright arm, the reed or reeds being attracted and repulsed by the upper end of the pole piece. Additional changes will be evident to those skilled in the art.

It will be understood that embodiments, variations and applications or uses other than those illustrated and described or indicated may exist without departing from the spirit and scope of this invention.

What is claimed is:

1. In electrical apparatus for controlling desired phases of the operation of a model railroad train, including an ofi-track circuit for super-imposing a modulated radio frequency current on a power current supplied to the track rails, said modulations being selectively controllable to different audio frequencies, and an on-track circuit supplied through said track rails and including power and control portions, said power portion including an engine drive motor, the improvement in the control portion of said on-track circuit which comprises a diaphragm; a plurality of reeds mounted on said diaphragm and adapted to vibrate in response to difierent audio frequencies; means for vibrating said diaphragm in accordance with said preselected audio frequencies; a switch having a relatively light resilient blade and a relatively heavy blade in position with respect to each said reed so that said light blade Will be vibrated by movement of that reed corresponding thereto and each said blade is spaced from the corresponding reed when said reed is at rest; a relay coil in parallel with each said switch; and means for controlling the speed and direction of movement of said drive motor and operable by said relay coils.

2. In electrical apparatus for controlling desired phases of the operation of a model railroad train, including an oil-track circuit for superimposing a modulated radio frequency current on a power current supplied to the track rails, said modulations being selectively controllable to different audio frequencies, and an on-track circuit supplied. through said track rails and including power and control portions, said power portion including an engine drive motor, the improvement in the control portion of said on-track circuit which comprises a diaphragm; a plurality of reeds mounted on said diaphragm and adapted to vibrate in response to different audio frequencies; means for vibrating said diaphragm in accordance with said preselected audio frequencies; a plurality of switches, each having a relatively light resilient blade and a relatively heavy blade in position with respect to each said reed, so that each said light blade will be vibrated by i movement of that reed corresponding thereto and each said blade is spaced from the corresponding reed when said reed is at rest; a relay coil in parallel with each said switch; and switches operated by said relay coils for controlling the speed and direction of movement of said drive motor.

3. In electrical apparatus for controlling desired phases of the operation of a model railroad train, as defined in claim 2, including two double-pole, single-throw switches, one switch being closed upon energization of one said relay coil and the other switch being closed upon energization of another said relay coil; a control motor operated in one direction when one said switch closes and in the opposite direction when the other said switch closes; a lead screw rotatable by said control motor and insulated therefrom; a variable resistance in series with said engine drive motor; a block movable by said lead screw and carrying a contact for changing said variable resistance; a snap action reversing switch, said engine drive motor being operated in opposite directions in accordance with the position of said snap-action switch; a conductor for supplying current to said lead screw and through said lead screw contact to said variable resistance; and a plunger mounted on said lead screw block for shifting said snap-action switch to an opposite position when said block is moved toward the end of said lead screw and the amount of said variable resistance is a maximum.

4. In electrical apparatus, a switch having a relatively light, straight and resilient blade and a second blade having a weight thereon adjacent the outer end, said light blade extending beyond said second blade and the outer end of said second blade being curved toward said light blade for contact therewith when said light blade is at rest; an insulating block for mounting said blades in generally parallel relations; a diaphragm and means for vibrating the same; a reed mounted on said diaphragm for engagement with the extending end of said light blade upon vibration of said reed; a relay coil; a source of current connected to said switch and said relay coil, with said switch and said relay coil in parallel; and a load circuit including a relay control switch operable in response to energization of said relay coil.

5. In electrical apparatus, as defined in claim 4, wherein the extending portion of said light blade is curved so that the end of said light blade is transverse to the remainder of said light blade.

6. In electrical apparatus, including a resonant relay and a switch therefore, an electrical circuit for receiving a modulated radio frequency, said modulations being selectively controllable to different audio frequencies, and a power controlled device, the improvement which comprises a vibrating member; a reed mounted on said member and adapted to vibrate in response to a predetermined audio frequency; means. for vibrating said member in accordance with a preselected audio frequency; a switch having a relatively light resilient blade and a relatively heavy blade in position with respect to said reed so that said light blade will be vibrated by movement of said reed, and said blade is spaced from said reed when said reed is at rest; a relay coil in parallel with said switch; and means for controlling said power controlled device and operable by said relay coil.

7. In electrical apparatus, including a plurality of resonant relays responsive to different audio frequencies and switches therefor, an electrical circuit for receiving audio frequency signals, said signals being selectively controllable to different audio frequencies, and a power controlled device, the improvement which comprises a vibrating member; a plurality of reeds mounted on said member and each adapted to vibrate in response to a predetermined audio frequency; means for vibrating said member in accordance with said preselected audio frequencies; a switch having a relatively light resilient blade and a relatively heavy blade in position with respect to each said reed so that said light blade will be vibrated by movement of that reed corresponding thereto and each said blade is spaced from the corresponding reed when said reed is at rest; a relay coil in parallel with each said switch; and means for controlling said power controlled device and operable by said relay coils.

8. 1n electrical apparatus, a member adapted to vibrate; a first switch having a readily movable blade and a relatively immobile blade normally contacting said readily movable blade, said readily movable blade extending to said member; electrical vibration means controlled by the said first switch; a reed adapted to be vibrated by said electrical vibration means; a second switch having a readily movable blade and a relatively immobile blade normally contacting said readily movable blade, said readily movable blade extending to a position adjacent said reed but spaced from said reed when said reed is at rest; a relay in parallel with said second switch, said second switch and relay being connected to a source of current; and a source of current connected to said first mentioned switch and said electrical vibration means, so that vibration of said member will cause said first switch to modulate current flowing to said electrical vibration means.

9. In electrical apparatus, a vibrator including a diaphragm and means for vibrating the same; a first switch having a relatively light blade and a relatively heavy blade normally contacting said light blade adjacent the end of said heavy blade, said light blade extending beyond said heavy blade and to said diaphragm; a second vibrator including a diaphragm and electrical means for vibrating said diaphragm and controlled by said first switch; a reed mounted on said second vibrator diaphragm; a second switch having a readily movable blade and a relatively immobile blade normally contacting said readily movable blade, said readily movable blade extending to a position adjacent said reed but spaced from said reed when said reed is at rest; a control relay actuated by said second switch, said second switch and control relay being connected to a source of current; and a source of current connected to said first switch and said electrical vibrating means of said second vibrator, so that vibration of the diaphragm of said first vibrator will cause said first switch to modulate current flowing to said second vibrator.

References Cited in the file of this patent UNITED STATES PATENTS 161,739 Bell Apr. 6, 1875 196,747 Edison Nov. 6, 1877 276,960 Currier May 1, 1883 937,285 Craft et al. Oct. 19, 1909 1,082,475 Orswell Dec. 23, 1913 1,352,266 Hirsch Sept. 7, 1920 1,834,103 Moon Dec. 1, 1931 1,872,372 Wensley Aug. 16, 1932 2,010,705 Stark Aug. 6, 1935 2,073,443 Cardoza Mar. 8, 1937 2,085,198 Lindsay June 29, 1937 2,163,195 Edwards June 20, 1939 2,176,600 Agnew Oct. 17, 1939 2,187,023 Forsman Jan. 16, 1940 2,352,556 Mathews June 27, 1944 2,388,531 Deal Nov. 6, 1945 2,420,232 Deal May 6, 1947 2,436,633 Curzon Feb. 24, 1948 2,511,766 Brailsford June 13, 1950 2,534,144 Price Dec. 12, 1950 FOREIGN PATENTS 261,384 Great Britain Oct. 6, 1927 517,971 Great Britain Feb. 14, 1940 

